The present invention relates to an electric appliance having a casing composed of two identically designed casing half shells mounted in mirror inversion to one another.
An electric appliance composed of two identically designed casing half shells is.
An appliance according to the definition of the species is described in from German Utility Model 296 06 759 U1, which describes a multipart casing in modular design to accommodate a circuit board. This is intended for a multipart casing for low-voltage switchgear, such as time relays, thermistor protective gear, for accommodating a circuit board. The casing here is divided into upper and lower casing parts parallel to the mounting plane. The circuit board is designed with stair-step gradations along two opposite edges and is equipped with cable connectors for connecting screw-type terminals designed in block form in the area of the stair-step gradations. In addition to contact pins, the cable connectors also have mounting pins, optionally designed as hook-shaped locking mounting pins.
German Patent 30 26 247 C2 describes a casing that can be lined up for mounting on a mounting rail. A circuit board having electric connecting elements arranged on its edges can be inserted into the casing. The connecting elements project partially out of the openings in the casing. The casing here is divided perpendicular to the mounting direction in the longitudinal direction of the casing.
An object of the present invention is to provide an electric appliance of the type described above by creating a casing having a simple, inexpensive design that is easy to assemble and has only a few parts parts, with the mounting accomplished by snap-on attachment without any impairment due to the usual distortion of the casing shells. This object is achieved in that the casing is composed of two identically built casing shells mounted in mirror inversion to one another. The separation joint formed by the two casing shells here does not pass through the integrally molded parts provided for the snap-on mount, so that distortion of the casing shells does not cause any problems in assembly.
An especially advantageous refinement of the present invention is achieved when the two casing shells are joined together by integrally molded catch elements.
An especially simple embodiment minimizing the number of details is achieved by implementing the snap-on mount by two spring locking hooks, one of which is integrated into each of the casing shells.
The embodiment having two identically designed casing shells that can be mounted in mirror inversion to one another can be achieved when the two casing shells in the mounted state form a separation joint which passes through the axes of symmetry of two opposing side walls and outside the spring locking hook.
An especially advantageous embodiment of the terminals, in particular their connection, is achieved when a circuit board having at least two terminal insulators is mounted in the interior of the casing, the terminal insulators being snapped into the circuit board and their terminal lugs belonging to the terminals being electrically connected to the circuit board by soldering.
In addition, it is advantageous when terminals are integrated into the electric appliance and when, for adding additional terminals for expansion, a terminal block can be locked onto in each case one side wall of the two casing shells, the terminal block having terminals into which slide the terminal lugs of terminal insulators projecting out of the casing when locked together.
Another advantageous embodiment of the present invention is achieved when the switchgear has on the front side at least one turning knob as an adjusting element having an adjusting security device, where a mechanically coded plate can be locked onto the turning knob, with the mechanical coding of the plate corresponding to a certain position of the turning knob.